How to Place Purlins along top of Roof Slope?

[artitech]

What would be the best way to add purlins running the length on top of these glulam frames? The purlins would be square to the roof slope (bottom edge same as top edge slope of glulam frames).

See attached (Revit 7.0).

[artitech]

...just to clarify

... the purlins would be running perpindicular to the frames, down the entire length of the structure.

[Steve_Stafford]

What would be the best way to add purlins running the length on top of these glulam frames? The purlins would be square to the roof slope (bottom edge same as top edge slope of glulam frames).

See attached (Revit 7.0).I don't have Revit 7.0 available.

I used two approaches both using massing as the underlying tool to establish the work plane since the framing doesn't lend itself to just using a face of the frames to do it. One method uses a curtain system whose mullion pretend to be framing and empty panels make it look like framing. The other is an in place roof family extrusion that sketches all the framing and voids to trim them up. I have a Revit 8 version of the file if you can use it?

See if either approach helps...

[SkiSouth]

...just to clarify

... the purlins would be running perpindicular to the frames, down the entire length of the structure.

Create a structural beam family for your purlin. Then set a reference plane to the slope of the frame, naming it left slope, right slope etc. Make the reference plane your work plane.
Draw the purlin down the length of the building. You can array or copy along the work plane if you wish, but you do not have to be accurate in spacing, as when finished, simply dimension the purlins, and they will properly space themselves.

Use this rough girt family to see it helps. To adjust the height of the girts or purlins, move the reference plane.

[Mr Spot]

Structural framing system is also another option to help contain all the framing to 1 or 2 elements. Was bit buggy in v7 though. So wouldn't attempt it unless you're using version 8.

Method is similar to Skisouth except you just draw the boundary for the beams and set the spacing and justification.

[patricks]

Create a structural beam family for your purlin. Then set a reference plane to the slope of the frame, naming it left slope, right slope etc. Make the reference plane your work plane.
Draw the purlin down the length of the building. You can array or copy along the work plane if you wish, but you do not have to be accurate in spacing, as when finished, simply dimension the purlins, and they will properly space themselves.

Use this rough girt family to see it helps. To adjust the height of the girts or purlins, move the reference plane.

Oh hey is that a Z-girt like used in metal buildings? We do alot of those, but I've always just modelled the roof with an 8" structure layer to represent the girt space, and then drawn them in as detail items on building sections.

As for the model originally posted, where you talking about placing a reference plane that runs along the surface of all those trusses? I think that might be kind of difficult, because it appears that the roof slopes diagonally (slopes down both towards the side and towards one end).

It would be nice if a reference plane could be defined by 3 points. Then if you needed a plane at an odd angle, you could just go to a 3D view and pick 3 points on objects in the model to define the plane.

[SkiSouth]

Oh hey is that a Z-girt like used in metal buildings? We do alot of those, but I've always just modelled the roof with an 8" structure layer to represent the girt space, and then drawn them in as detail items on building sections.

Yes. It is a simple 8" girt. No parametrics.




As for the model originally posted, where you talking about placing a reference plane that runs along the surface of all those trusses? I think that might be kind of difficult, because it appears that the roof slopes diagonally (slopes down both towards the side and towards one end).


Depends on every roof situation. No different than the actual construction of the building. To accomplish the working plane, simply section the building 90 degrees to where you want the reference plane, then using the draw tool, define the reference plane. The simplest thing (and most accurate), if the roof is a straight forward slope is to use the select tool and let revit set the reference plane.

[artitech]

All good approaches... it goes to show that their is always more than one way to accomplish the same task.

It is the reference plane that was baffling me... I'll give it a try using the variety of methods mentioned. The massing may be the key, that's how I made the form to attach curtain wall and roof systems to already anyway (attached image).

[Steve_Stafford]

...It would be nice if a reference plane could be defined by 3 points. Then if you needed a plane at an odd angle, you could just go to a 3D view and pick 3 points on objects in the model to define the plane...That's what massing lets you accomplish plus it stays available to change geometry later if necessary.